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<table width="100%" summary="page for cushny"><tr><td>cushny</td><td align="right">R Documentation</td></tr></table>

<h2>
A data set from Cushny and Peebles (1905) on the effect of three drugs on hours of sleep, used by Student (1908)
</h2>

<h3>Description</h3>

<p>The classic data set used by Gossett (publishing as Student) for the introduction of the t-test.  The design was a within subjects study with hours of sleep in a control condition compared to those in 3 drug conditions.  Drug1 was 06mg of L Hscyamine, Drug 2L and Drug2R were .6 mg of  Left and Right isomers of Hyoscine.  The detal1, delta2L and delta2R are changes from the baseline control.  
</p>


<h3>Usage</h3>

<pre>data(cushny)</pre>


<h3>Format</h3>


<p>A data frame with 10 observations on the following 7 variables.
</p>

<dl>
<dt><code>Control</code></dt><dd><p>Hours of sleep in a control condition</p>
</dd>
<dt><code>drug1</code></dt><dd><p>Hours of sleep in Drug condition 1</p>
</dd>
<dt><code>drug2L</code></dt><dd><p>Hours of sleep in Drug condition 2</p>
</dd>
<dt><code>drug2R</code></dt><dd><p>Hours of sleep in Drug condition 3 (an isomer of the drug in condition 2</p>
</dd>
<dt><code>delta1</code></dt><dd><p>Change from control, drug 1</p>
</dd>
<dt><code>delta2L</code></dt><dd><p>Change from control, drug 2L</p>
</dd>
<dt><code>delta2R</code></dt><dd><p>Change from control, drug 2R</p>
</dd>
</dl>



<h3>Details</h3>

<p>The original analysis by Student is used as an example for the t-test function, both as a paired t-test and a two group t-test.  The data are also useful for a repeated measures analysis of variance.  
</p>


<h3>Source</h3>

<p>Cushny, A.R. and Peebles, A.R. (1905) The action of optical isomers: II hyoscines.  The Journal of Physiology 32, 501-510.
</p>
<p>Student (1908) The probable error of the mean.  Biometrika, 6 (1) , 1-25.
</p>


<h3>References</h3>

<p>See also the data set sleep and the examples for the t.test</p>


<h3>Examples</h3>

<pre>
data(cushny)
with(cushny, t.test(drug1,drug2L,paired=TRUE)) #within subjects 

error.bars(cushny[1:4],within=TRUE,ylab="Hours of sleep",xlab="Drug condition",main="95% confidence of within subject effects")
</pre>


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